There are display devices known in the related art that adopt a method whereby an image formed at a transmission-type optical image forming element constituted with a liquid crystal panel or the like is made visible to the eye by illuminating the optical image forming element from the rear surface. The user of such a display device observes an optical image transmitted through the optical image forming element. The display brightness of a display device adopting this method is improved by raising the brightness of illuminating light (i.e., light provided through the backlight system). Patent reference literature 1 discloses a display device that includes a backlight unit constituted with a cold-cathode fluorescent lamp and a light emitting diode array and provides a bright display by raising the brightness of the illuminating light.
Patent reference literature 1: Japanese Laid Open Patent Publication No. 2003-140110